The former leader of Iran was 86 years old, in failing health, and facing increasing internal opposition despite repeated crackdowns. By killing him, the US turned him into a martyr, not just for hardcore loyalists in Iran, but for many others across the entire Middle East. And his replacement not only has political, ideological, and religious motivation, but: the US made it personal.
Assuming Mojtaba is not a vegetable he lacks religious credentials, has no charisma and hereditary ascension cuts against a core tenant of the Islamic revolution. What having him in place makes bare to Iranians is the IRGC is running the country as a mafia state and he is its puppet.
Thanks to incompetent drunk Pete Hegseth, the US bombed a school and killed a lot of little girls. That won't be forgotten for a long, long time. Not only has it enraged much of the population, but it undercut the opposition movement by providing fresh evidence that the US isn't and has never been on the side of the Iranian people.
More Iranians are enraged over the prospect of being abandoned as bombs stop falling. Iranians supporting attacks against the regime were well aware of the fact there would be collateral damage. There were never any safe options no matter what. On one hand you have unintentional mistakes and on the other deliberate regime massacres involving orders of magnitude more people coupled with omnipresent systematic terrorizing of the population.
The parade of unhinged threats from Trump has been an absolute gift to Iran's strategic and tactical military planners. if the ceasefire holds for a while, they can use the time to bolster defenses in at least some of the right places, because Trump gave them a target list. Politically, it nicely demonstrates to everyone -- including US allies -- that Trump is a psychotic moron who cannot be trusted. I think at this point that if he decides to pull the US out of NATO, they might offer to hold the door open for him. He is quite clearly demented AND insane: it's obvious on inspection.
Trump's rhetoric is certainly idiotic and highly counterproductive.
Bottom line: the US lost in every possible way, and provided a textbook counterexample to the principles expounded in The Art of War.
What is interesting is the degradation of Iranian terror networks throughout the region. Hezbollah's days in Lebanon appear to be numbered. PMFs facilities in Iraq are under attack. The Houthis know they won't be getting Iranian support any time soon and rather than exporting terror huge numbers of their proxies around the world are flooding the streets of Iran.
No better way to enhance a regimes legitimacy than a bunch of foreign paid mercenary boots on the ground at the behest of the regime.
We've seen a similar unraveling of Russian proxies due to their preoccupation with getting their asses kicked in Ukraine. The fall of Assad's Syria, loss of influence in Caucasus and Africa, abandonment of Transnistria.
There's a reason Iran wants to be paid in cryptocurrency, aka fake money for criminals. Do you know which country really REALLY wants cryptocurrency, lots of it? Which country has knocked itself out running numerous large-scale operations to get it? North Korea. That's the reason: Iran no doubt already has a deal in place for weapons, and the North Koreans are happy to supply them because they've very interested in finding out how those weapons perform in live combat against the US military.
North Koreans have been supplying weapons to the Russians for years. There is no need for any of this just to sell weapons or find out how weapon systems perform in real world conditions.